If you are developing a #WebApp try to enable #CSP heders directly from the start. It is much easier to validate correct function everytime a feature is added and not at a later point if the app still works correclty.
That said: #angular made it easier to add CSP headers with a nonce https://angular.dev/best-practices/security#content-security-policy
I trust you with searching on how to configure your webserver and check CSPs with tools ;)
I found this refrence rather helpful: https://content-security-policy.com/
